DESIGN OF ELECTRON-OPTICAL SYSTEMS FOR IMAGE TUBES IN BEIJING INSTITUTE OF TECHNOLOGY

The design procedures of electron optical system for image tubes can generally be classified into three categories: 1. Direct design (method of analysis), involving a solution for the field and computation of electron trajectories from the given structural and electrical parameters of the electron optical system, then determining the electron-optical image characteristics of the system; 2. Inverse design (method of synthesis), contrary to the direct design, it involves setting up the electron trajectories and the field from the required electron optical imaging characteristics and then determining the structural and electrical parameters of the system; 3. Automatic design (method of optimization), involving the construction of a function of evaluation (objective function) and putting forward the restrainment conditions from requirements of electron optical imaging system, making a search for the structural and electrical parameters of the system satisfying the restrainment conditions that make the objective function as small as possible. We will synoptically describe our work in image tube design making use of the above three methods in Beijing Institute of Technology (BIT). A flow chart is shown in Fig. 1.